Got a tip for us?
Let us know
Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
Anyone has tested El Capitan in a RAID 0 machine?
- Thread starter Lolito
- Start date
- Sort by reaction score
There's no point to it. You won't see any speed increase OS-wise as neither the boot up or app launching takes advantage of that much bandwidth. OSX currently boots at around 170MB/s.
If you need a RAID-0 use it for accessing very large files or as a scratch disk.
If you need a RAID-0 use it for accessing very large files or as a scratch disk.
Does 10.11 DU support OSX Raid or Concatenated Disks (ie a spanned volume)? What didn't work when you first tried it?
I haven't tried that in the Core Storage world yet...but I wouldn't do so unless there was some real advantage to overcome the inherent greater risk of running a spanned volume.
I haven't tried that in the Core Storage world yet...but I wouldn't do so unless there was some real advantage to overcome the inherent greater risk of running a spanned volume.
You can determine it two ways ( there are more but...)
- divide the amount of RAM in use by the boot up time (which starts around 1-2 seconds after the chime).
- or clone the OS from one drive to another. Your cloning app such as Super Duper will tell you the average speed it takes to transfer system files across the SATA interface.
In both cases it's around 170MB/s. That's why you can hardly make OSX boot faster if you go from a SATA2 SSD to a SATA3 SSD or PCIE.
If you could boot the OS from a hibernation file (Windows supports this) you would get very fast boot speeds because a large file like that would saturate the SATA bus easily. It can even saturate a 2GB/s connection.
that's as good as it gets unless you could boot one up in a virtual machine with a disk activity monitor to see the data rate
Current versions of OSX boot at an average effective rate of 170MB/s because most of the files that transfer into memory are quite small. Far too small to saturate a SATA3 interface or a PCIE-based SSD.
I've booted OSX with single XP941, single SM951, a triple SM951 RAID 0 (capable of reading 2300MB/s) and Samsung 850 Evo. They all booted in the same time : 11-12 seconds.
What a load of rubbish. Things don't just get pulled into RAM on boot and then stay there, static throughout the boot process. Processes load and complete before the boot finishes (freeing their memory), other processes will use much more memory and then release it, temporary use of memory will grow and then be released.
Your calculation is not accurate.
If data is released from memory that's irrelevant because we are only measuring the transfer of data from disk to memory. It's an average boot speed of 170MB/s and yes, it's accurate. There's benchmarks done by a number of sites that confirm it and we've been looking at those benchmarks on the Mac Pro forum for months.
Last edited:
I use it on a RAID 0 and it's been fine. I have it with two Samsung 830s on a Sonnet Tempo Pro. The only caveat is that if you want to wipe or work with the raid drives you have to do it in a different OS X disk utility. I'm not sure if any of the recent releases have included a disk utility that can work with raid setups.
My RAID 0 works fine in 10.11GM.
And it seems I use RAID 0 because of the same reason as you do - make it a single large partition rather than 2 small partition. The speed increment is just a bonus.
But again, My RAID 0 was created in Yosemite, but not 10.11 (AFAIK, there is no native apps to do that at this moment).
And it seems I use RAID 0 because of the same reason as you do - make it a single large partition rather than 2 small partition. The speed increment is just a bonus.
But again, My RAID 0 was created in Yosemite, but not 10.11 (AFAIK, there is no native apps to do that at this moment).
thanks for the answers. I see you guys are on mac pro, not macbook like me. I´m not sure, but your machines have hardware raid, not software raid like mine, right? I might be wrong on that.
Di you guys did a clean install? did you desactivated system integrity...
truth is that being a beta, and try to put all the risky things in, it is normal that it just would brick. I will just wait for official release or for .1 or .2 when it's more stable.
Di you guys did a clean install? did you desactivated system integrity...
truth is that being a beta, and try to put all the risky things in, it is normal that it just would brick. I will just wait for official release or for .1 or .2 when it's more stable.
I am using software RAID (setup via disk utility). The hardware RAID card is an expensive optional equipment, not all Mac Pro have it.
My 10.11 is not clean, I have a backup boot disk and I just upgrade that to 10.11. So it can show me the real picture (or problem) when I want to upgrade my current boot drive.
The RAID 0 works regardless if SIP is on / off.
My 10.11 is not clean, I have a backup boot disk and I just upgrade that to 10.11. So it can show me the real picture (or problem) when I want to upgrade my current boot drive.
The RAID 0 works regardless if SIP is on / off.
Yeah, mine is done using disk utility as well. I've actually done it two different ways. Initially I upgraded from 10.10 (which i did a clean install of at the time) so I didn't change the RAID setup. Later on I did a clean install but had to wipe the RAID (I just re-created it instead of formatting it's partition) but had to set it up on another drive with Mavericks.
What does the average transfer throughput have to do with your original assertion that "OSX currently boots at around 170MB/s"? How is copying system files even a remotely comparable operation to booting an OS?
Except that you aren't measuring that. You'd be measuring that if the boot process consisted, exclusively, of copying data from disk to RAM, but it doesn't.
Running fine here as well on software RAID0. 10.11GM clean install on 2x128 GB Samsung PCIE SSDs in a Mac Pro.
Hi CDivander,
i also want to upgrade my Mac Pro Yosemite installation at a software raid to El Capitan. The setup is similar to yours.
Mac Pro 2009 with the special firware upgrade from 4.1 to 5.1 for additinoal CPU support etc. and two Samsung SSD connected to a SATA 3 controller. All is working performant with Yosemite.
Now i've created a boot stick which is not being recognized by the Mac Pro, same stick works perfect at a 2011 Macbook Pro. Did you perform a clean install? And if yes, did you have to recreate the software raid and how did that work? At the first OS Utilities screen i did not find a terminal (i guess you have to do the raid configuration at a terminal session since EL Capitan has removed graphical tools).
Would be great if you could share your experiances.
Regads Rilak
Hi Rilak!
Yes i did a clean installation. However I created the RAID with Disk Utility in Yosemite on a separate drive. And I launched the installation from that drive as well, so I didn't need to create a boot stick.
So if you have a spare drive to run Yosemite on, you might be able to use the same method.
Good luck!